About Juboury Fitness Tracker: ✔Fully compatible with IOS and Android smartphones which with bluetooth version 4.0/4.0+.(1)IOS:OS system should be IOS8.0 or above.(2)Android:Os system shoud be Android 4.3 or above. ✔Lightweight and portable wearble pedometer frees your pocket,check the data on your wrist during workout and dailylife use. ✔A Fitness tracker that recording your steps and tracking the distance properly,calculating the consumption of calories by arm swing. ✔A Monitor which with basic sleep monitor function can show your sleep state in the app.Sedentary reminder call you stand up for a relaxation. ✔A smart watch that show the time and date, with alerts for SMS or call so you can keep up to date at all times. Specifications: ✔Bluetooth Version: V4.0 ✔Band Size: Adjustable,fit for 5.5inches to 7.8inches wrist ✔Battery: 75mAh, lithium ion polymer battery ✔Charging Mode: Standard charge on USB port or PC by poping the host out ✔Charging Time: 45 minutes ✔Standby Time: 5-7 days Package Includes: ✔1 x Juboury Fitness Tracker ✔1 x User Manual